Compound steam-engine.



No. 812,199. PATENTED FEB.13, 190s.

R. P. GIBBONS. COMPOUND STEAM ENGINE.

APPLICATION FILED FEB-4, 1903.

2 SHEETS-SHEET 1.

Wkivxesses 1N VEN TOR EMLWQMJL RM Ema-Mum mfovneg UNITED STATES PATENTOFFICE.

ROBERT PEARCE GIBBONS, OF KOPA, NEW ZEALAND.

COMPOUND STEAM-ENGINE. i

Specification of Letters Patent.

Patented Feb. 13, 1906.

Application filed February 4, 1903. Serial No. 141,923.

To all whom it may concern:

Be it known that I, ROBERT PEARCE GIB- BONS, a subject of the King ofGreat Britain, residing at Kopa, Provincial District of Auckland, NewZealand, have invented new and useful Improvements in Compound Steam-Engines and I do hereby declare the following to be a full, clear, andexact description of the same. i

This invention relates to the construction of the cylinders andvalve-chests of compound steam-engines and to the means for supplyingthe steam to the first or high-pressure cylinder and from it to theothers.

The invention has been devised in order to economize the space taken upby the engines and to obtain the greatest amount of power possible fromthe steam. In most of the compound engines at present in use the steamin passing from one cylinder to the other has to travel through arelatively long distance, thereby losing a certain percentage of itsefficiency, while in my present inven-v tion the object has been toprovide an engine in which the steam may pass directly out of onecylinder into the next, thus saving such loss in efliciency.

In carrying out the invention the whole of the cylinders are formed,preferably, in one casting, the divisional pieces being made ofsuflicient thickness to allow of steam-valve chests of special formbeing formed therein. These valve-chests consist of circular holesextending throughout the lengths of the cylinders and paralleltherewith. At the ends of each of these valve-chests ports are formedthat extend from each end of one cylinder across to the correspondingend of the next cylinder. The slide-valves consist of plungers that fitclosely within the chests and are adapted to be moved up and downtherein, so as to alternately. open and close the ports at each end, andthus serve to admit the fresh steam to the first cylinder and to passthe exhaust from such cylinder on to the next, and so on.

Special means have been devised whereby the proper relative movements ofthe cylinder-pistons and slide-valves of all the cylinders may bemaintained;

In order, however, that the invention may be properly understood,reference will be made to the accompanying sheets of drawings, in which-Figure 1 is a vertical section through the centers of the cylinders.Fig. 2 is a sectional plan taken on the line 1 2 of Fig. 1. Fig. 3 is atransverse section taken approximately on the line 3 4 of Fig. 2. Fig. 4is a diagram showing the relative positions of each cylinders crank.Fig. 5 is a diagrammatic view illustrating the principle of operation ofthe appliances devised.

In illustrating the invention I have shown it as applied to threecylinders but it will be readily understood that the appliances employedmay be adapted to any desirednumber of cylinders.

a, b, and c are the three cylinders, c being the high-pressure, b theinteimediate, and c the low-pressure. These cylinders are all preferablymade in the one casting d and are provided with covers a, fitted ontheir top V ends.

f represents the pistons, which are formed in the ordinary manner andoperate the cranks and crank-shaft through the rods g. The relativepositions of thecranks to which each of the rods 9 are connected areshown in Fig. 4, where h is the hi h-pressure crank, the intermediate,and if the low-pressure. This arrangement of cranks will insure theproper relative working of each of the pistons m, n, 0, and pare thesteam-chests, which consist of circular recesses made in the casting (Zand which extend parallel to and throughout the same length as thecylinders. The first of these steam chests m has ports 1" at each endthat open into a steamchamber 8, to which steam is conducted from thesource of supply. It has also ports 7" at each end that open into eachend of the'highpressure cylinder a and which serve to admit the steamfrom the chamber 8 alternately to each side of the piston in suchcylinder. The second steam-chest n is provided with two ports 7" at eachend that open, respectively, into the two ends of the cylinders a andI), while the third steam-chest 0 has its ports at each end opening,respectively, into the cylinders b and c. The last chest 1) has itsports opening, respectively, into the cylinder 0 and into a chamber t,that is in communication with. the outer air on to appliances for whichthe exhaust-steam may be required.

The steam-chests m, n, 0, and p have fitting within them plungers u, w,:0, and y, respectively. These plungers are so arran ed as to closelyfit within the chests and to be iiee to move up and down therein. Theends of these plungers are so formed as to provide free steam-passageswhen any of the ports 1". To the top ends of the plungers rods 5 areconnected. These rods pass upward through suitable glands in the coversof the cylinders and have their top ends connected to the ends ofrocking beams 6 and 7, mounted upon a shaft 8, that is supported inbearings 9, secured to the top of the cylinder-casting. To this shaft 8a reciprocatory motion is imparted by means of the lever 10, secured toits end and to which a connecting-rod 11 is attached. Thisconnecting-rod is connected to the eccentric-rod 12 or to crank or linkmotion. The reciprocatory motion of the shaft 8 will thus impart arocking motion to the beams 6 and 7.

The rocking motion of the beams 6 and 7 will impart the necessaryslide-valve motion to the plungers a, w, 00, and y, and in order thatthese plungers shall move in their proper relative order the plungers aand w are connected to opposite ends of the beam 6, while the plungers0c and y are connected to the opposite ends of the beam 7. This mannerof connecting will insure that the plungers a and a", shall be at theupmost limit of their to open the bottom ports of the steam-chests m and0, while the plungers w and y shall be at the bottom limit of theirmovement, so as to open the top ports of the steam-chests n and p. Onreferring to the diagrammatic view Fig. 5 the reason for thisarrangement will be made clear, as this figure shows the relativepositions of the cylinderpistons in regard to each other and to thepositions of the different plungers, whose positions relatively to eachother are also indicated.

The steam led to the chamber 8 from the source of supply is admittedalternately to the two ends of the cylinder (1 by means of the movementof the plunger m. The plunger n then allows for the exhaust of thiscylinder being admitted to the cylinder 1) alternately at each end,while the plunger 0 in its working alternately opens and closes its ortsat each end, so as to allowof the exaust-steam passing from thecylinder 1) into the respective ends of the cylinder 0. Theexhaust-steam from the cylinder 0 is allowed to escape into the chamber25 by means of the working of the plunger p.

What I claim as my invention, to secure by Letters Patent, is

1. A compound engine comprising a plurality of cylinders and pistonstherein arranged adjacent to and parallel with each other, cranks forsaid pistons successively spaced in such manner that the crank for thelarger piston precedes, the crank for the next smaller piston byapproximately one hunstroke, so as and desire such ends are oppositedredand ninety degrees, an admission-valve and chamber for the high-pressurecylinder, an exhaust-valve and chamber for the lowpressure cylinder anda valve and chamber between each cylinder of the seriesbut out of linetherewith, each cylinderbeing connected by ports at each end with thevalvechambers preceding and following in series, and a common operatingmeans for all the valves, said means actuating alternate valves in theseries in-opposite directions in timed relation to the operation of thepistons and in such manner that each valve will open the inlet-port toits piston before the piston completes its stroke.

2. A compound engine comprising a plurality of cylinders andpistonstherein arranged adjacent to and parallel with each other, cranks forsaid pistons successively spaced in such manner that the crank for eachpiston precedes the crank of the next succeeding piston by approximatelyone hundred and ninety degrees, an admissionvalve and valve-chamber forthe initial cylinder of the series, an exhaust-valve and valve-chamberfor the terminal cylinder, and a valve-chamber and valve arrangedbetween each cylinder and the one succeeding in the series, eachcylinder being connected by ports at its opposite ends with thecylinders preceding and following in the series, and a common operatingmeans for all of the valves, said means constructed to actuate alternatevalves in opposite directions in timed relation to the reciprocation ofthe pistons and in such manner that each valve will open the inlet-portto its cylinder before the piston therein completes its stroke.

3. In a compound engine the combination with the cylinders arrangedalongside each other and connected at each end by ports leading to thecylinders immediately preceding and following in the series, the endcylinders of the series being provided respectively with admission andexhaust ports, pistons in said cylinders and connected with the shaftsby cranks which are alternately substantially opposite each other,piston-valves seated in the cylinder-bodies and adapted to control saidports, a rock-shaft extending across the cylinder-heads and arms securedthereto and extending oppositely and each connected with one of thevalves.

. In testimony whereof I have signed this specification, this 23d dayOfDecember, 1902, in the presence of two subscribing Witnesses.

ROBERT PEARCE GIBBONS.

